A torque fluctuation absorber is a device arranged on a power transmission path from an engine to a transmission for absorbing, or reducing, a torque fluctuation between the engine and the transmission. A known torque fluctuation absorber includes a damper portion for absorbing the torque fluctuation with a spring force, hysteresis portion for absorbing, or reducing, the torque fluctuation with a hysteresis torque caused by a friction, and a limiter portion configured to slip when the torque fluctuation caused by a torsion between rotating shafts exceeds the amounts absorbable at the damper portion and the hysteresis portion. According to a known torque fluctuation absorber disclosed in JP2009-293652A, the damper portion is arranged on the power transmission path at a position closer to the engine and the limiter portion is arranged on the power transmission path at a position closer to the transmission, in order to make an inertia at a portion before reaching a spring of the damper portion to be low and the inertia at a portion alter the spring to be high, for defining a damping performance of the damper portion.
A structure for improving a distribution balance of the inertias between the portions before and after the spring of the damper portion is complex with the known torque fluctuation absorber due to having plate members with intricacies in, for example, shapes and placements. The known torque fluctuation absorber includes bolts, or connecting members, for connecting the torque fluctuation absorber and the engine member, disposed on the power transmission path closer to the engine at a position inward in a radial direction of the damper portion. As a result, through-holes are provided to multiple plate members for penetrating the bolts, causing the structure to become complex.
A need thus exists for a torque fluctuation absorber, which is not susceptible to the drawback mentioned above.